The Fairleigh Dickinson University poll conducted shortly before the U.S. Supreme Court cleared the way for states to legalize sports betting found that 50 percent of Americans favor it, with 37 percent opposed.

"Sports betting is about two things: It is about legalizing what millions of Americans already do every day (and) it is about intensifying the engagement of a nation of sports fans," said poll director Krista Jenkins, a professor of political science at the New Jersey university. "It will now be a race to see who can benefit the most and the earliest from this changed landscape."

Supporters say people are doing it anyway (which 57 percent of supporters said), and cite extra tax revenue to states as benefits (52 percent.)

Opponents fear expanding sports betting will lead to more people with gambling problems; 66 percent of opponents listed that concern as a reason for their disapproval. Other concerns among opponents are worries about the spread of organized crime (43 percent) and concern over the integrity of the games (39 percent).

Ruling Monday on a case from New Jersey, the court struck down a ban on sports betting in all but four states. It allowed individual states to pass laws legalizing sports betting.

A big unanswered question is whether the sports leagues will be able to force gambling companies or states to share part of the proceeds with them. The major professional sports leagues are pushing for a so-called "integrity fee" to help reimburse them for the costs of monitoring betting and looking for suspicious actions or betting patterns. The companies and most states strongly oppose this, although the leagues are making some headway in negotiations with individual states.

A majority of respondents to the poll (62 percent) say the sports leagues should not get a cut of the proceeds, compared to 32 percent who support that.

The poll of 1,001 adults was conducted by landline and cellular telephones from April 25 to May 1, and has a margin of error of plus or minus 3.9 percentage points.